The present invention relates to an anti-lock hydraulic automotive brake system.
German patent application 44 25 578 discloses an anti-lock automotive brake system wherein a pneumatic brake force booster which is operable irrespective of the driver's pedal actuation and a master brake cylinder connected downstream of the brake power booster are connected to an ABS hydraulic unit which has a pump and to which the individual wheel brakes of the vehicle wheels are connected. Upon the entry into brake pressure control, the brake force booster is actuated independently of the driver in order to precharge the wheel brakes, and further pressure increase in the wheel brakes is effected by means of the pump upon completion of the precharging operation.
The known brake force booster has a complicated construction and requires corresponding electrical actuating provisions for the actuation of the control part in the brake force booster by independent force.
An object of the present invention is to improve an anti-lock automotive brake system of the type mentioned hereinabove to such end that the pump can be precharged quickly by applying relatively simple means.